[Freeswitch-users] Wrong jitter in the RECV_RTCP_MESSAGE event

[Alexander Haugg]

Hi,

Codec = PCMU
Wireshark RTP analyse:
Jitter in the Wireshark max=2,9 ms; mean=0,57

But the last RECV_RTCP_MESSAGE event show this:
==========================================
SSRC: 0eb0e841
NTP-Most-Significant-Word: 3724642770
NTP-Least-Significant-Word: 4165677056
RTP-Timestamp: 14487886
Sender-Packet-Count: 1409
Octect-Packet-Count: 225440
Last-RTP-Timestamp: 14487924
RTP-Rate: 8000
Capture-Time: 1515653966925374
Source0-SSRC: 7c1b0ae5
Source0-Fraction: 0
Source0-Lost: 0
Source0-Loss-Avg: 0
Source0-Highest-Sequence-Number-Received: 32561
Source0-Jitter: 159
Source0-LSR: 2311973851
Source0-DLSR: 63014

And the last RTCP event from the Wireshark show this:
=============================================
Real-time Transport Control Protocol (Sender Report)
    10.. .... = Version: RFC 1889 Version (2)
    ..0. .... = Padding: False
    ...0 0001 = Reception report count: 1
    Packet type: Sender Report (200)
    Length: 12 (52 bytes)
    Sender SSRC: 0x0eb0e841 (246474817)
    Timestamp, MSW: 3511979744 (0xd1548ee0)
    Timestamp, LSW: 2709503779 (0xa17fbf23)
    [MSW and LSW as NTP timestamp: Apr 16, 2011 21:55:44.630855000 UTC]
    RTP timestamp: 3435008682
    Sender's packet count: 3257276450
    Sender's octet count: 4258211364
    Source 1
        Identifier: 0x463e7aa2 (1178499746)
        SSRC contents
            Fraction lost: 248 / 256
            Cumulative number of packets lost: 1105247
        Extended highest sequence number received: 1972857173
        Interarrival jitter: 1013423106
        Last SR timestamp: 1007735790 (0x3c10d3ee)
        Delay since last SR timestamp: 108449976 (1654815 milliseconds)
[RTCP frame length check: OK - 52 bytes]


1.       What is the formula to get the jitter in ms from the rtcp? I can’t find anything in the web, or I can’t recognise the answer.

2.       What is wrong, the RECV_RTCP_MESSAGE event or the RTCP from the receiver?

If I have the answer to the first question, i can answer the second question by my self ;-)

Thanks a lot!!!

By the way, it is the newest FreeSwitch from yesterday.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.freeswitch.org/pipermail/freeswitch-users/attachments/20180111/5d2bf752/attachment-0001.html>